Control apparatus



April 21, 1931. Y B. o. AUSTIN 1,801,837

CONTROL APPARATUS Filed April 12, 1926 mess INVENTOR 1 v Baswm 014051971 A'TTORNEY Patented Apr. 21, 1931 UNITED STATES PATIEIN'Pv OFFICE VAN IA PENNSYLVANIA, ASSIGNOR T0 WESTING COMPANY, A CORPORATION OF PENNSYL- CONTROL APPARATUS Application filed April 12, 1826. Serial No. 101,568.

My invention relates to control apparatus and more particularly to arc-rupturing devices of the type generally used for breaking circuits of high amperage.

The object of the invention, generally stated, is the provision of an arc-rupturing device that shall be simple and eflicient in operation and readily and economically manufactured.

A more s ecific object of the invention is to provide or the establishment of concentrated local magnetic fields in arc-rupturing devices, to control the travel of arcs during the disrupting process.

A further object of the invention is to provide for the utilization of the current that flows in arc horns to build up local concentrated magnetic fields to restrict the travel of arcs.

It is also an object of this invention to provide, for the concentration and utilization of the magnetic force built up during the disrupting process, to oppose the tendency of the main arc-rupturing field to reverse the direction of travel of an are, when it reaches the end of the arc horn.

Other objects of the invention will in part be obvious and in part appear hereinafter.

The invention accordingly, is disclosed in the embodiment thereof shown in the accompanying drawing and comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth and the scope of the application of which will be indicated in the claims.

For a more complete understanding of the nature and objects of the invention reference should be had to the following detailed description taken in connection with the accompanying drawing, in which Fig. 1 is a view in side elevation of an arc-rupturin device with parts removed to show one em odiment of a device constructed in accordance with this invention,

Fig. 2 is a perspective view of a modification of the invention showing features of the construction,

Fi 3 is a view in section taken along the lme IIIIII of Fig. 2 and,

Fig. 4 is a view in section of the preferred form of the device taken along the line IVIV Fig. 1.

Referring now to the drawing, the illustrated arc-rupturing device is of a wellknown type and comprises a frame-work 1 on which is mounted a stationary contact member 2 and a movable contact member 3, the latter being disposed on a plunger 4 of an air engine 5 which may be any wellknown type used for operating such devices. In this particular construction, are horns 6 and 7 are associated with the contact members 2 and 3, respectively. As shown, the arc horns are disposed to receive arcs that may be drawn between the contact members.

Since the contact member 3 is movable, the arc horn 7 is also mounted to move with the plunger 4 of the air engine 5. Accordingly, the contact member 3 and are horn 7 are set in fixed relation so that an arc will not be obstructed in travelling from the contact member to the arc horn by a variable and wide air gap.

As is usual practice in arc-rupturing devices of this type, an electromagnet 8 is provided for developing a main arc-rupturing field to cause arcs drawn between the con tact members 2 and 3 to travel outward onto the arc horns 6 and 7 and finally disrupt them. The electromagnet may be of any suitable type and in this case, as shown in the drawing, it comprises a core 9 encircled by the lead-in conductor 10. V

Ordinarily, during the operation of an arcrupturing device of this type, when an arc reaches the ends of the arc horns the magnetic field which has been developed by the electromagnet 8 tends to reverse the direction of travel of the ends of the arc and to I force them backward along the outer faces of the arc horns. This is particularly true in the case of the lower arc horns and the continual flashing of the arcs into the operating mechanism reatly reduces the life of the arcrupturing d evice.

In order to protect the operating mechanism of the arc-rupturing device from the destructive action of the arcs, means capable of building up concentrated local magnetic fields may be associated with either the upper or lower arc horn. In this particular construction, the means for providing a concentrated local field is shown associated with the lower arc horn, but it will be readily understood that such a device may beprovided in conjunction with the upper arc horn.

As shown in Fig. 1, the lower arc horn has mounted. thereon, a magnetizable member 11, which in this embodiment of the invention is a plate counter-sunk in the top face of the arc horn. In order to substantially complete the magnetic circuit, pole-pieces 13 are disposed on opposite sides of themagnetizable' erative relation with them;

In operation, when an arc has been delivered to the arc horns 6 and 7, the main magnetic arc-rupturing field developed by the electromagnet 8 tends to cause the arc to move outward and to increase its length until it breaks. When the end of an arc reaches the end of the lower arc horn 7, it tends under the influence of the main magnetic field to travel along the outer or lower face of the arc horn toward the operating mechanism of the arc rupturing device. 1 7 The current travelling in the arc horn 7 will induce in the plate 11 and the pole pieces 13a magnetic flux which builds up a con- 7 centrated magnetic field, located adjacent horn.

to the lower side ofthe arc horn and which will flow in a direction opposite to that of the main magnetic field. Consequently, when the end'of the arc reaches this local field, its travel inward toward the operating mechanism isstopped andit leaves the arc Since the plate 11, as it moves with the arc horn 7 is always located between the pole pieces 13, a local magnetic field which will oppose the travel of an arc inward along the lower face of the horn isbuilt up as soon as the arc has travelled far enough outward along'the horn to cause a current toflflow through the section of the horn extending between the pole pieces. In this manner the desired localmagnetic field is established before the arc reaches the end of the arc horn.

In Fig. 2 a modified type of archorn is illustrated. In this particular construction,

the arc'horn 15 simulates a platewhich has.

been folded to form two substantially parallel curved arms 16 and 17 In order to provide the local magnetic field, a U-shaped magnetizable member 18 is mounted upon the lower arm 16 of the arc horn. The member 18 may be retained in position in any suitable manner such, for example, as by riveting plates 19' to the inner faces of the U- shaped member that extends below the arm 16.

When a U-shaped magnetizable member, such as shown in Fig. 2, is provided, there is no need of pole pieces since the desiredlocal magnetic field flows between the arms extending below thev member 16. When are horns of this type are used, they function in the same manner as the arc horn illustrated in Fig.1 and build up a local magnetic field below the'arc horn to restrict the travel of the end of the arc. 1

Since various changes in the above .described construction and arrangement .of parts and different embodiments oftlie invention may be made without departing from the-scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings, shall be interpreted as illustrated, an'd'not in a limited sense. 7

I claim as my'invention:- 1. In an arc-rupturingdevice, in combination, an arc horn, and means comprising magnetic material for concentrating lines of magnetic forceto providea local magnetic fieldon the outside of the archorn to restrict the travel of the endjof an arc rearwardly on the arc horn.

2. An arc-rupturing device comprising, in

combination, a plurality of contact members disposed for relative movement, electromage netic means for developing a magnetic field cooperative to rupture an arc drawn between the contact members, a magnetic conductor carried by one of the contact members, and

pole pieces disposedfadjacent to said magnetic conductor to concentrate lines of magnetic force induced by'current flowing in the arc horn to build up a local magnetic field to restrict the travel of an arc rearwardly on the arc horn. x r p 3. An arc-rupturing device'comprising, in combination, a plurality of contact members disposed for relative movement, mechanism for operating the arc horns, are horns disposed to receive an arc'from said contact members, one of said arc horns being movable, means for providing an'arc5rupturing field capable of forcing an arc outward along the arc horns, pole pieces disposed on opposite sides of the movablearc horn, and'a magnetizable member carried by the movablearc its of an arc along the outer face of the arc horn toward the operating mechanism.

4. In an arc-rupturing device, in combination, an arc horn for receiving an arc, and a member of magnetic material carried by the arc horn for concentrating lines of magnetic flux to provide a local magnetic field, said member being disposed on the arc horn to locate the local magnetic field in a position to prevent the travel of an arc rearwardly on the arc. horn.

5. An arc-rupturing device comprising, in combination, an arc horn for receiving an arc, and means carried by the arc horn for concentrating lines of magnetic flux to provide a local magnetic field, said flux concentrating means being disposed to locate the local magnetic field on the outer side of the arc horn to prevent the travel of the arc rearwardly on the arc horn.

6. In an arc-rupturing device, in combination, an arc horn for receiving an arc, and a U-shaped member of magnetic material carried by the arc horns, the legs of said U-shaped member extending beyond the arc horn to concentrate lines of magnetic flux to provide a local magnetic field adjacent the outer side of the arc horn to prevent the travel of an arc rearwardly on the outer face of the arc horn.

In testimony whereof, I have hereunto subscribed my name this 10th day of April, 1926.

BASGUM O. AUSTIN. 

